Self Focusing Binoculars, Fixed Focus & Individual Focus Binoculars

Always in Focus Binoculars

Manufacturers using terms like Self Focusing binoculars, or as they also sometimes use: Auto Focus Binoculars is somewhat misleading.

If they wanted to use a marketing type term, they should really go by the names like individual, fixed focus, focus free binoculars, or at least something like always in focus binoculars.

I say this because these devices don't actually auto or self focus at all and there is no mechanism that automatically does this for you. This is just marketing companies hyping them up and in the process confusing everyone!

They are actually basically what I would describe as being permanent focus binoculars that have no focusing mechanism at. These have been designed to have a fixed but really long depth of view (usually from around 40ft to infinity) and thus they are said to have a large hyperfocal distance.

What this means is that everything from usually about 40 feet to infinity will remain in focus.

Individual Focus Binoculars with Diopter Adjusters on both eyepieces

Individual Focus Binoculars

However whilst you do get some permanently fixed focus binoculars with no focus mechanism at all, these completely no focus binoculars cannot allow for any sort of differences in the strength of vision between your eyes.

So what are far more common are those that most manufacturers term as being Individual Focus Binoculars.

These don't have a single focus wheel and mechanism that simultaneously adjusts the focus on both sides of the binocular as you get on normal instruments and which most of you will be familiar with. Instead they have two diopter adjusters - one on each of the eyepieces that enable you to alter the focus of each side of the binocular independently.

However this must not be looked at in the same way as the main focus wheel on a standard binocular. These dioptric correction rings are there to calibrate the binocular to your particular vision and thus allow for any differences in your left and right eyes.

How do "Auto Focus Binoculars" Work?
In order to make a binocular that needs no main focus adjustment, they are designed to focus on distant objects with a very long depth of view.

Thus their optics are designed so that they use your eyes natural ability to focus and so I suppose you can see where the marketing terms of auto focus or focus free came from.

To set the fixed focus binocular to your particular eyesight, you adjust the diopter of each eyepiece to your vision (which is why they are also referred to as individual focus bins). Once you have completed this step, they require no further adjustments. That is unless someone with a different strength of eyesight wants to use them, your vision changes or your setting is moved by accident.

Why all the confusion with the names?
The confusion in the name and the tag of self focusing binoculars has probably been brought about by clever marketing strategies from the major manufacturers of this type of binocular trying to make them sound more sophisticated than they actually are. What ever you wish to call them, Fixed focus, or always in focus binoculars have been around for over a few decades now they have their uses and there are some excellent quality binoculars of this type out there.

What are the Advantages Self Focusing Binoculars?

The fewer amount of moving parts means they are much easier to make and therefore tend to be cheaper, more robust and therefore often much longer lasting. This also makes them much easier to make fully dust and waterproof. So as you can see a fixed focus pair of binoculars would be ideal for uses in harsh environments and so make popular military as well as marine binoculars.

Less parts also means that they are oftem more lightweight than standard instruments.

Because of the fact that once you have set the binoculars to your vision and no further focusing is necessary, it does make using them quicker than binoculars where you have to focus on every object you look at. This is perfect for fast moving erratic objects, so in theory they could make ideal birding binoculars, so long as a good close focus distance is not important to you (Fixed focus optics usually have minimum close focusing distance of around 35 - 40ft).

The lack of a focussing wheel make the binoculars much less complicated and therefore are a lot easier to use, which is great for kids, elderly people and if you are wearing thick gloves for example. So once again ideally suited for cold or harsh environments and make ideal Skiing Binoculars and again ideal for marine use in colder climates.

Disadvantages of Auto Focus Binoculars

Always in Focus Binoculars sound great, but are considered to be a compromise in design, suited for convenience, but not well suited for work that falls outside their designed range or uses.

Auto focus binoculars (fixed focus) do not usually have a very close range and many will only focus from about 35 to 40 feet and that is why they tend to be more popular for use in wide open areas like the ocean so are ideal for Marine Binoculars and would not be suitable where a close minimum focusing distance is important - Butterfly Binoculars for example.

Fixed focus binoculars rely on the flexibility of your eyes to keep the image clear and in focus. This is not a problem for children and young adults, but as you get older the eye slowly loses its ability to focus and so for many people over the age of about 40, these binoculars could produce a lot of eye strain.

Self focussing binoculars do have their place and uses, but because you set them to you individual vision, they are less suitable for sharing with others (unless you have the same vision) So don't take them to share with someone else at a sporting event or safari holiday for example.

Jason Binoculars

Automatic Focusing Binoculars were initially made popular by the brand "Jason" which was established in 1947 in Kansas City. The Jason brand made a group of self-focusing binoculars that became very popular in the 1970's and early 80's. The Jason brand of binoculars was then bought by Bushnell who have now re-branded them as their PermaFocus line of auto focus binoculars. As far as I know, Jason Binoculars are no longer in production.

Great quality optics and coatings in combination with very large 56mm objective lenses and a moderate 8x power results in a binocular that is able to deliver the brightest images in extremely adverse light conditions.

These attributes as well as many others make this binocular not only suitable but excel in a wide range of uses and times where light is a limiting factor. This includes hunting, security, general wildlife, birding, marine and astronomy.

The 7x50 configuration, tough body designed to withstand the elements as well as it's bright image, wide field of view and of course the rangefinding reticle, digital GPS and compass mark these Celestron binoculars out as the ideal companion for boaters, security and military personnel as well as hunters and especially those involved in search and rescue operations.

The fixed focus compact roof prism binoculars, come with a very comfortable open bridge design and are fully waterproof and filled with nitrogen gas to prevent internal fogging. They have a very wide field of view and produce a high quality image that makes these ideal take anywhere binoculars.

The New Bushnell 7x50 Marine Binoculars (13-7507) are designed for boating, but can be used in any demanding environment or where rock-solid durability is required. Not only are they completely waterproof, but they actually float and come with a host of features that includes a digital compass for true heading and range finding scale that allows you to estimate the range to objects of a known size.

The Steiner 7x30 Navigator Pro C Marine Binoculars are waterproof, have anti glare and haze optics, come with an integrated range finder and stabilized compass, are lightweight and compact, making them ideal for any small marine vessel. These focus free binoculars have Steiner's Sports Auto Focus system that keep all objects in focus from about 20 yards to infinity that allow faster location of navigational marks.

A tough, solid compact binocular that offers plenty of magnification, rainproof construction and maximum versatility. Refined design after years of use in a variety of settings, from mountaintops to deep canyons, aboard and ashore. For spotting game or exploring natureís majesty, Steinerís increased depth-of-view puts all the action in focus at once. Long eye-relief for eyeglass wearers.